Am 06.05.2014 22:44, schrieb Chris:
On Tuesday, 6 May 2014 at 17:10:39 UTC, Ary Borenszweig wrote:
On 5/6/14, 10:41 AM, Chris wrote:
On Tuesday, 6 May 2014 at 13:25:56 UTC, Ary Borenszweig wrote:
On 5/6/14, 8:23 AM, bearophile wrote:
Paulo Pinto:
You can think of Julia as a dynamic language similar to Python, with
optional typing and for such a young language, a quite good JIT
compiler backed by the LLVM backend.
Unlike dynamic languages, at running time all variables are strongly
typed.
What do you mean?
Just a wild guess: that the compiler infers the type of a variable and
turns it into a static type. That would increase the security during
runtime (plugins, libraries, crackers).
Julia doesn't have a compiler. There's no compile-time and run-time
distinction. But functions are jitted before execution.
I know. I was talking about JIT compilation. There must be some kind of
(jit) compiler.
I don't see how that means "variables are strongly typed". If you mean
that at runtime they carry their type information, so do dynamic
languages.
But are the types immutable at runtime (in other dynamically typed
languages) or can they be reassigned as in
x = "Hello"
x = 5
If yes, then I think this is what Julia is addressing, that a module,
library or malevolent cracker cannot reassign a different type to a
variable.
x = 5 // Error!
If so,
They can be re-assigned (http://forio.com/julia/repl/):
julia> x = "Hello"
"Hello"
julia> x = 5
5
julia>
Julia compiler works in a similar way to Self, Strongtalk, Dylan, Lisp
and so on.
The language is dynamic, with optional type annotations and the compiler
does its best to infer the types.
The design of the language is done in a JIT friendly way, while keeping
its dynamic capabilities.
--
Paulo
